Twitter’s swift attempt to stop the graphic images from spreading represents a change for a platform that has had a more lax policy towards sensitive content compared to other social sites.

But even as hashtag #ISISMediaBlackout trended on Twitter, some other users said blocking the images is detrimental as well.

Meanwhile, the U.K.’s Metropolitan Police Service said its Counter Terrorism Command is investigating the contents of the video. In an attempt to stop the spread of the video in the U.K. – the militant on the video spoke with a British accent – the Met released a statement saying that “viewing, downloading or disseminating extremist material within the UK may constitute an offence under Terrorism legislation.”